style.css

* {
  box-sizing: border-box;
}

html, body {
  padding: 0;
  margin: 0;

}

.board {
  padding: 1rem;
  background-color: #f0f0f0;
  border: 1px solid #ccc;
  margin: 10px;
  height: fit-content;
}

@keyframes highlight {
  0% {background: yellow;}
  100% {background: #fff;}
}

.card {
  cursor: grab;
  user-select: none;
}

.slot {
  border: 1px dotted #ddd;
  padding: 10px;
}

.view-mode, .edit-mode {
  margin: 10px 0;
  padding: 1rem;
  border: 1px solid silver;
  background-color: #fff;
  border-radius: 1rem;

  animation: highlight 1s ease-in 1;
}

#container {
  display: flex;
}

button {
  font-size: 2rem;
  cursor: pointer;
}

.hide {
  display: none;
}

.translucent {
  opacity: .2;
  display: none;
}

.dragging {
  position: absolute;
  width: 250px;
  height: 53px;
  margin: 0;
  cursor: grabbing;
  transform: rotate(5deg);
  top: 0;
  left: 0;
}

.dragging .view-mode {
  box-shadow: 2px 2px 5px rgba(0,0,0,.3);
}

.droppable {
  background-color: lightyellow;
}

.card.shadow {
  border: 1px dashed #ccc;
  background-color: rgb(255, 255, 158);
  height: 53px;
  border-radius: 1rem;
}